Rock drill



Aug. 3 1926.

G. M. NELL' ROCK DRILL 4 Filed April 14,, 1922 2 Sheets-Sheet 1 u e M r m a ,594,426 M. NELL I ROCK DRglLL Filed April 14, 1922' 2 sheets-sheet 2 Patented Aug. 3, 1 926.

PATENT orrlce GUSTAVE M. NELL, OF DENVER, COLORADO, ASSIGNOR TO THE DENVER ROCK DRILL MANUFACTURING COMPANY, 01 DENVER, COLORADO, A CORPORATION OF DELA- WARE.

ROCK DRILL.

Application filed April 14, 1922. Serial No. 552,537.

The present invention relates more particularly to the chuck rotating mechanism of. rock drills of that type in which a motor independent of the drilling motor is employed for effecting the rotation.

The primary ob ect is to provide a motor structure and driving mechanism between the motor piston and the chuck that isv simple, effective, readily accessible and mounted so -as to reduce friction and undue strain.

The preferred embodiment of the. invention is illustrated in the accompanying drawings, wherein Figure 1 is a plan View of a rock drill with the steel rotatingmotor illustrated in section.

Figure 2 is a longitudinal sectional View,

Figure 3 is a sectional view on the line 3-3 of Figure 1,

Figure 4: is a sectional View on the line H of Figure 2.

In the form of structure shown, the drilling motor may be of any desired form and includes a barrel 5 in which a hammer piston 6 reciprocates, said piston having a hammer extension that operates through a head 8. A

chuck housing or hood 9 is mounted on the front end of the head 8, and contains a rotatable chuck sleeve 10. This sleeve is provided with an angular socket 11 to receive the rear end of a drill steel 12. It will be understood that the hammer extension 7 of the piston 6 is adapted to strike the rear end of the drill steel 12 and that the rotation of the sleeve will effect the rotation of said steel.

Formed on the housing or hood 9 and preferably integral therewith is the piston chamber 13 of the chuck rotating motor. Said chamber has an open side closed by a removable head 14. Rotatably mounted in the said chamber 13 are intermeshing gear pistons 15 and 16. Motive fluid from any suitable source and controlled by any well known means is admitted to the chamber 13 through a port 17, while the exhaust is permitted through an outlet 18.

Extending rearwardly from the chamber and concentrically with the gear piston 16 is a bore 19, and a holding bolt 20 for the removable head 14 passes axially through the piston 16 and bore 19, its rear end being provided with the usual holding nut 21 that is preferably held by a lock washer 22 and bears against a closure plug 23 for the rear end of the bore 19. Another holdingbolt.

24, passing through the head 14, also passes axially through the piston element 15, and

surrounding said bolt'2t, is a bushing 25. Interposed between the bushing 25 and the piston element 15 are suitable roller-bean them. The shaft 27 carries a worm 32 whichis in mesh with a worm wheel 33 having a clutch connection with the chuck sleeve 10. This clutch connection preferably includes a collar 34 slidably and relatively non-rotatably mounted on the chuck sleeve 10 and having ratchet teeth 34 that interlock with corresponding teeth on the worm wheel 33. It will thus be evident that when the gear pistons are driven motion will be transmitted through the shaft 27, the worm 32, worm wheel 33 and clutch mechanism 3 1 to the chuck sleeve 10. The motor, it will be evident is of simple structure, and the parts thereof readily accessible. The holding bolts for the removable head of said motor constitute supports for the gear pistons and for the driving shaft. The shaft 27 while interlocked with the piston element 16 is free to move longitudinally thereof. The gear piston is thus relieved from the thrust of said shaft due to the worm 32 and said thrust is taken by the thrust bearing 31.

From the foregoing, it is thought that the construction, operation and many advantages of the herein described invention will be apparent to those skilled in the art, without further description, and it will be understood that various changes in the size, shape, proportion and minor details of construction, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a rock drill, the combination with a drill steel actuating motor, of a rotatable steel holding chuck sleeve, and a motor for rotating the sleeve, said motor comprising a cylinder member having a piston chamber, a removable head for the piston chamber, coacting gear pistons in the chamber, a driving connection between the gear pistons including a drive shaft connected to one of the gear pistons, and holding bolts for securing the head on the cylinder member, said gear pistons and shaft surrounding and being journaled to rotate around said bolts.

2. In a rock drill, the combination with a drill steel actuating motor, of a rotatable steel holding chuck sleeve, and a motor for rotating the sleeve, said motor comprising a cylinder member having a piston chamber, a removable head for the piston chamber, coacting gear pistons in the chamber, a driving connection between the gear pistons including a drive shaft having a slidable interfitting connection with one of the gear pistons, a holding bolt on which said shaft is journaled, and a thrust bearing for said shaft at the end thereof opposite its connection with the gear piston.

3. In a rock drill, the combination with a drill steel actuating motor, of a rotatable steel holding chuck sleeve, and a motor for rotating the sleeve, said motor comprising a cylinder member having a piston chamber, a removable head for the piston chamber, coacting gear pistons in the chamber, a tubular worm connected to one of the gear pistons and having gear connections with the chuck sleeve, holding bolts passing axially through the gear pistons and worm, and anti-friction bearings for said gear pistons and worm surrounding the bolts.

4. In a rock drill, the combination Witha drill steel actuating motor, of a steel holding chuck sleeve rotatably mounted thereon, a chuck sleeve rotating motor comprising a cylinder member having a rear wall and a front open side, a removable head for said open side, a rotatable piston member in the cylinder member having a shaft extending through the rear Wall and geared to the chuck sleeve, and a boltfor securing the head in place on the cylinder member, said bolt passing axially through the piston member.

In testimony whereof, I affix my signature.

GUSTAVE M. NELL. 

